Inside Toyota Motor Corp.’s oldest plant, there’s a corner where humans have taken over from robots in thwacking glowing lumps of metal into crankshafts. This is Mitsuru Kawai’s vision of the future.

“We need to become more solid and get back to basics, to sharpen our manual skills and further develop them,” said Kawai, a half century-long company veteran tapped by President Akio Toyoda to promote craftsmanship at Toyota’s plants. “When I was a novice, experienced masters used to be called gods, and they could make anything.”

These gods, or Kami-sama in Japanese, are making a comeback at Toyota, the company that long set the pace for manufacturing prowess in the auto industry and beyond. Toyota’s next step forward is counter-intuitive in an age of automation: Humans are taking the place of machines in plants across Japan so workers can develop new skills and figure out ways to improve production lines and the car-building process.

So at first glance, it seems that Toyota is going against the grain of manufacturing in high-wage developed economies. The usual story is that the manufacturing that remains in the States or Japan or Western Europe is highly automated. The workers in such systems are highly productive since they oversee lots of expensive machines. In effect, such manufacturing can stay in a high cost location because the actual labor content per unit is relatively small.

There are, of course, exceptions to this. We recently posted about Harley Davidson, which has revamped its manufacturing while keeping its workforce more or less in tact. That is partly due to how they have branded themselves but also makes sense because they are using those workers to provide variety. That is, they are producing a such a variety of bikes at relatively low volume that automating everything is infeasible. (See also this post on Insignia Athletics making baseball gloves in Massachusetts.)

But what Toyota is doing is different. Toyota isn’t offering the variety of Harley or Insignia. These guys are banging out crankshafts which should be the same on every car. So what is Toyota trying to do here?

Learning how to make car parts from scratch gives younger workers insights they otherwise wouldn’t get from picking parts from bins and conveyor belts, or pressing buttons on machines. At about 100 manual-intensive workspaces introduced over the last three years across Toyota’s factories in Japan, these lessons can then be applied to reprogram machines to cut down on waste and improve processes, Kawai said.

In an area Kawai directly supervises at the forging division of Toyota’s Honsha plant, workers twist, turn and hammer metal into crankshafts instead of using the typically automated process. Experiences there have led to innovations in reducing levels of scrap and shortening the production line 96 percent from its length three years ago.

Toyota has eliminated about 10 percent of material-related waste from building crankshafts at Honsha. Kawai said the aim is to apply those savings to the next-generation Prius hybrid. …

“We cannot simply depend on the machines that only repeat the same task over and over again,” Kawai said. “To be the master of the machine, you have to have the knowledge and the skills to teach the machine.”

So Toyota is trying to do something that is very Toyota. This is fundamentally about continually improving the process — making sure that people have a deep understanding of the process so they can think of ways of making it better. The implementation of those changes may result in reprogramming machines on other lines, but the genesis of the changes is with the humans.

Another aspect of this is that the Toyota Production System is fundamentally about experimentation. There is a hypothesis that the current process is the best and experiments are done to see if that is true. When the hypothesis is proven wrong the process is updated and the whole thing starts over. Using humans not only has more people thinking about process changes, it also provides flexible resources that execute the experiments.

A final point. More people deeply involved in process improvement gives more opportunities to develop leaders in running TPS. As the article notes, when Toyota went through its embarrassing recall over sudden acceleration several years ago, a common diagnosis was that it had grown too quickly without enough management depth. Having more workers living daily with the production process opens up the possibility of building a deeper bench of talent.